The study, conducted by Peter Nelson, M.D., Elahe Mostaghel, M.D., Ph.D., and Bruce Montgomery, M.D. from the Fred Hutchinson Cancer Research Center and University of Washington, suggests that cancer cells may develop the capacity to produce their own androgens with the help of the androgen-synthesizing proteins.
In the study, tests were conducted on tumours removed and preserved from deceased prostate cancer patients during "rapid autopsies" immediately after death.
During the course of treatment all the patients had received androgen-blocking therapies to suppress tumour growth.
The analysis made the team detect the key proteins in the tumours, or enzymes, needed for a cell to produce its own testosterone from cholesterol present in the cell.
"This study, along with other research in the field, suggests that cancer cells may have the ability to adapt and produce their own androgens that permit these cancer cells to survive," said Nelson.
"While this study does not prove that the cancer cells act in this way, it does show it is possible," he added.
In order to deprive cancer cells of the hormones that fuel their growth androgen-deprivation therapy is routinely used in the treatment of advanced (metastatic) prostate cancer.
However, cancer cells become 'androgen independent' over time and grow even in the presence of the medications.
New medications are being clinically tested with the goals of blocking androgen synthesis.
Abiraterone, for example, inhibits the enzymes in the metabolic pathways, which convert cholesterol to androgens, and work by blocking androgen synthesis in adrenal gland and possibly in the tumours themselves